反应详情

A solution of but-3-yn-1-ol (10.00 g, 143 mmol) in dichloromethane (310 mL) was treated with dihyropyran (18.10 g, 215 mmol) and pyridinium p-toluene sulfonate (3.60 g, 14.30 mmol). The reaction mixture was stirred at room temperature for 4 days. Water was added and the layers were partitioned. The organic layer was washed with brine, dried over magnesium sulfate, filtered and evaporated under reduced pressure. The crude material was purified by flash chromatography on silica gel using 1:1 ethyl acetate: heptane to give 21.57 g (98%) of the title compound. 1H NMR (CDCl3, 400 MHz) δ 4.65 (m, 1H), 3.90-3.80 (m, 2H), 3.60-3.50 (m, 2H), 2.50-2.45 (m, 2H), 1.95 (m, 1H), 1.90-1.80 (m, 1H), 1.79-1.10 (m, 1H), 1.65-1.50 (m, 4H).

1. customthe layers were partitioned
2. washThe organic layer was washed with brine
3. dry with materialdried over magnesium sulfate
4. filtrationfiltered
5. customevaporated under reduced pressure
6. customThe crude material was purified by flash chromatography on silica gel using 1:1 ethyl acetate